Grinding machine



Feb. 19, 1935. A Q PUMMER 1,991,771

GRINDING MACHNE Filed April 5, 1955 3 Sheets-Sheet 1 www www GRINDING MACHINE Filed April 5, 1955 5 Sheets-Sheet 2 3 Sheets-Sheet 5 Feb. 19, 1935. A. G. PLIMMER GRINDING MACHINE Filed April 5, 1955 Patented Feb. 19, 1935 STATES f PATENT OFFICE 1 3 Claims. (Cl. Y791-27) This `invention.relates ^to..-improvements in machine-.tool structures. and` .especially toimprovements Viii-reversingv `mechanismsfor usef therewith.

An fobject fof the. invention, thereforei is the provision of` an n.improved v rever-sing mechanism for :reversingthe .drive =to..fa,-slidab1e part of a machine tool 'organizationsfor example,.the Work 1 supporting ,table- ,of- ;.a:..,grinding machine.

Another fobiect :of .the L.invention .is the 4provision-.ofmeansrfor effectingia tarry or pauseat or prior-.toseachf reversal` of .the direction Iof movement .of .the pant.` v

A1 further .object of the invention .is the provision ofsuch -a ymechanism: that may be .readily adjusted for l.varying-the'.duration of ,the pause or tarry.

A stillafurtlrier .object of the. invention. is'- the provision of -anadjustable, .terry -mechanism that Can-beapplied to :an existingand .well-.known reversing.mechanism.without .requiring an'extenswore-organization .or completemodication of said reversing :.structure.

Other objects and .advantages .of the .present invention should .be readily. apparent by reference to .the fo l1owing`..specication considered in conjunction. with vthe.. .accompanying drawings, forminga part thereof, and-it is Ytobe understood that .any modifications may be. made in'` 'the exact structural details .there'shown-fand. described, Within thescope v.ofY the .appended l claims, without departing.from-: orexceeding the `spiritof the invention..

Infthe.drawingsv v Figure 1 is a front elevationof agrinding machine .embodying l.the,improvemrnts `of this `;in vention.

Figure '2.is. a fragmentary :sectional .,viewtaken i on line 2 2 of'Figure .1.

Figure.. 3. is,a .sectional view taken on .line 3f3 of ..-Figur,e 2. A

Figure 4 is fa ,fragmentary Asectional viewY taken on line-4 4 of,Eig11re.ji2..

Figure. 5 vis afragmentarysectional view .take on 1ine ..5-.5 of Figure 4.

Figure fis. a fragmentarysectional .view taken on-line.6.-6fof.Figure 1.

Figure .7. is fa fragmentary sectionalview .taken on line .7-.7 of =Figure3.

`'Ivhroughout .the several .Views of the drawings similar reference characters are employed tol denote ythesaxne or -similar ..parts.

As was noted. above, this invention ,has applioation toimachine .tool structures-generally.. and

5 particularly .tothegmecha'nism for ,reversing the ,chine to the front thereof.A

directionof movement of a Work supporting table s of agrinding machine. The drawings disclose the .invention as applied to such a machine and asY there shown .the rmachine comprises a b ed 10 having formed on the upper surface thereof a flat and a V- guideway 11` and 12 `on which is mountedlawork supporting table 13. Extending rearwardly from the Ybed 10 is an extensionv 14 having formed thereon guideways15for a grinding Wheel carriage 16. Rotatably. mounted in the carriage 16 .is av spindle supporting at` its outer end a grinding Wheel 17. The'wheel 17 is enclosed within a suitable guard 18 secured to the carriage 16 and employed to confine the ,coolantusual v with vgrinding machines. Y

The spindle is provided intermediate its bearings with a pulley orsheave for the flexible transmission belt or belts 19 Whichare in turn trained about a pulley or sheavesecuredto a shaft 20 extending from the .primemover ormotor 21. The motor 21 is secured to the bed extension 14 and in.v addition to rotating the grinding, wheel and its spindle rotates through va sprocket chain transmission 22 the slidable gears of a change feed box mechanism secured to the rear Aend of the b ed extension 14. vThis change gearbox is not illustratedwin the .drawings since it may be of any we11-known-construction throughwhich the. drive ishad toa transverse shaft 23, see Figure 4, extending from the rear of the ma- The forward Vend of the shaft 23 is splined to a bevel pinion 24 `rotatably journaled in a bracket .25 carried bya housing 26 in turn secured to the reversing plate 27. Also journaled` in the bracket ,25 i s a sleeve28 to one end of which is keyed or otherwise secured a bevel pinion 29 meshing with thebevel gear 24. The other end Y of .the sleeve 28 lhas formed integral .therewith a spurpinion ,30. which meshes with the larger gear 3 1 of acompound gear V32 loosely journaled on a, shaft 3 3 carried` by the housing 26.. AThe sleeve 28 aheadof theA spur gear 30 has formedVV thereon clutch teeth 3.4 adapted to engage similar clutch teeth formedon the opposed face. of as lidinggear 36. The .gear 361s splined ,as at 37 to a drive shaft 38 whichhasits one Vend journaled in the sleeve 27 and'its other end in bearings 39 provided ,by the reversing plate 27. Meshing with the gear 36 Ais the small pinion 40 ofthe compoundgear 3 2, as shown in Figure 4, but it is to be understood that the .gear36 may beshifted to disengage it from the pinion .40and tointerrnesh theclutch teeth 34 `and 35.

In order to shift theclutchgear 35-.'-36, it is provided with a circumferential groove 41 receiving the free end 42 of a shifter fork 43 pinned or otherwise secured to a shaft 44 journaled in the housing 26. rlihe shaft 44 projects beyond the housing 26 and has secured to its projecting portion a shift lever 45 carrying at its upper end a knob 46, see Figure 1, and at its lower end a spring pressed detent 47 co-operating with sockets 48 carried by the forward face of the housing 26. From the foregoing it will be noted that the driving shaft 38 may be driven directly through the clutch teeth 34 and 35 at the same rate of speed as the shaft 23, or may be driven through the back gear at a much slower rate o-f speed.

The shaft 38 has loosely journaled thereon intermediate the bearings 39 a pair of oppositely facing bevel pinions 49 and 50 respectively having formed on opposed faces clutch teeth 51 and 52. Keyed to the shaft for slidable movement relative thereto and intermediate the gears 49 and 50 is a clutch member 53 having formed on opposite faces thereof clutch teeth 54 and 55. The clutch teeth 54 are adapted to engage with clutch teeth 51, while the clutch teeth 55 are adapted to engage with clutch teeth 52 whereby, depending upon the position of the clutch 53, one or the other of the gears 49 and 50 is positively rotated.

Meshing with the gears 49 and 50 is a relatively large bevel gear 56 keyed or otherwise secured to a worm shaft 57 rotatably journaled in bearings provided by the reverse plate 27. ntermediate the ends of the worm shaft 57, there is provided a worm 58 which meshes with a worm wheel 59 loosely mounted on a vertical shaft 60. The shaft 60 is journaled in bearings 61 and 62 provided by the bed 10 and the said shaft has secured to its upper end a rack pinion 63 meshing with a rack 64 attached to the under surface of the table 13.

Also loosely journaled about the shaft 60 is a bevel gear 65 meshing with a pinion 66 pinned or otherwise secured to the inner end of a shaft 67 rotatably journaled in the reverse plate 27, The outer end of the shaft 67 has pinned or other- Wise secured to it a silent chain sprocket 68 having trained thereabout a chain 69 in turn being trained about a sprocket 70 formed integral with or secured to a sleeve 71. The sleeve 71 is journaled on a shaft 72 carried by a bracket member 73 that is attached to and extends upwardly above the reverse plate 27. Secured as by a key or otherwise to the sleeve 71 is a hand wheel 74 which through the transmission just described constitutes a manual means for actuating the work table 13.

In order to connect either the power drive or manual drive with the table, the following mechanism is employed. The shaft 60 has extending through it at a point between the worm wheel 59 and bevel gear 65 a pin 75 carrying on projecting ends rollers 76.` The rollers 76 are disposed in elongated perforations 77 formed through a clutch member 78 surrounding the shaft 60 and disposed intermediate the said worm wheel 59 and bevel gear 65. The clutch member 78 has formed on one end thereof clutch teeth 79 adapted to engage clutch teeth 80 formed on the gear 65. On the other end the clutch 78 is fo-rmed with clutch teeth 81 adapted to engage clutch teeth 82 provided by a clutch member 83 associated with the worm wheel 59. The clutch member 83 forms in effect a portion of a safety friction clutch drive which comprises the said member 83, a disc 84, friction members 85, and springs and screws 86. The clutch 78 is shifted to its extreme positions to engage either clutch teeth 79-80 or clutch teeth 81-82 and for which purpose it has formed circumferentially thereof a groove 87 which co-operates with the nose 88 of the clutch shifter lever 89. 'I'his lever is adapted vto be oscillated about the axis of its pivot shaft 90 by means of the lever 91 which projects beyond the forward face of the reverse plate 27. From the foregoing it will be noted that the table may either be driven by power or actuated manually by merely shifting the clutch 78. It Will also be noted that when the manual means is in engagement the power means is disconnected and conversely when the power means is in engagement the manual drive is broken.

The means for shifting the table reversing clutch 53 comprises a shifter fork 92 carrying rollers 93 disposed within a circumferential groove 94 formed in the' said clutch. 'I'he shifter fork is mounted on a bar 95 secured in the walls of a reverserplate cover 105. Secured to the upper end of the fork 92 is a U-shaped spring cage 96 through the arms of which is slidable a rod 97. Secured to the rod intermediate its ends is a dog 98 having formed thereon oppositely inclined cam faces 99 and 100.

Encircling `the rod 97 and disposed on opposite sides of the dog 98 are springs 101 and 102 contacting with adjacent faces of the dog 98 on one end thereof and contacting on the other end with the arms of the U-shaped frame 96. is adapted to shift the rod 97 and compress the springs between itself and the said arms of the frame 96. In order to shift the said dog there is provided an arm 103 to which it is pivotally secured'intermediate its ends, the arm being also pinned or otherwise secured to a shaft 104 journaled in the cover plate 105 of the reversing plate 27. The shaft 105 extends beyond the cover 105 and has keyed orvotherwise secured to its projecting portion a reversing lever 106 which extends upwardly above the reverse plate and parts carried thereby. As seen in Figure 2. the lever 106 has projecting from it toward the bed and table an abutment 107 adapted to normally lie betweenopposed reversing -dogs 108 and 109. The dogs 108 and 109 are adjustable along a dog rail 110 provided on the forward face of the table 13 and are positioned at a distance representative of the length of the work, so that the said dogs contact with the abutment 107 and shift the lever 106 when the grinding wheel reaches the said ends of the work.

The spring frame 96 is inclined to move simultaneously with the movement of the dog 98 and the compression of the springs 101 and 102, but this movement is restricted' or prevented by latch members 111 and 112 being pivoted as at 113 to bosses 114 projecting inwardly from the cover 105. For this purpose the latches have formed intermediate their ends a shoulder 115 adapted to engage with their respective arms of the U-shaped spring frame 96. The free ends of the latches 111 and 112 are respectively provided with cam faces 116 and 117 adapted to be engaged respectively by "the cam faces 99 and 100 of the dog 98 for releasing the latched engagement and permitting the springs 101 and 102 to expand or fire, thereby shifting the clutch shifter fork 92 from one position to the other.

In practice it is frequently desirable that a tarry be effected in the movement of the work table prior to the reversal thereof, so that a The dOg 98v engage' thesaidfA ar'mofithe?fraineiwhenreleased' by# trie shoulder 115aridiwiliftnerefere; limiiffthe movement* of the frame" and consequently *the shifter fork-'upon release. This movement-is dsigneilv to neutralize ithe clutch 553 thereby stoppin@'thepowerdrive tothe taloleand arresting 'upon 'inwhichfdi'rection Y-the spring franie' 96 Iis '-to' be shifted.

'Disposed respectively Within `the eylinzleis-"12H8 with fa cl-eckvalye inlet 138 and`7139 Y permitting the in flx ofair-into'thecylinderwhen the heads thereof are moving away'fromtheir` respective hydr'alic circuit orfsystem.A "The l'pis'to'ris and piston 'rods 13411-1376 and '7135"137v are respectivelyprovded -WithfportsllO-:and 141 lwi'iich reu spectivelyitrniinate in atransve'rsep'ort l42"an"cl tlfi"e'1"said.t 'exhaust portsV` 140 "or-1 141J and? 142.

cover 105.

1'11` arid 112." In' order, theifrejto faccrtly' position the said latches, abutments 154 and155f are providd'to 1Vlimit ther'noveinent' of thef se'condarylatches 118 arid of-ftheir`fspringsy l i Theopertionlfof-the y'parts is Y asr follows: As-

thesalidjlever.v `'Ilie oscillation of? the reversing" lever will, through the clutch-shifting lever 1051,v compress-one of `the clutch springs 101 and102' springs `180`-or131. Asrlsoon as these-spring'sfaie` suflici'ently compressed* the dogf- 98 which-""walsf efiectinglthe compression ofthe springs ll'and 102-"will, throught its cam faces 99 or i 10m-release the primary leien 111 or 112 whieh islhbidingi the spring'frai'ri'. Upon'release' of"thisijame,y

it Will: moveI under the viiifluericepfits compressed spring, which 'rr'iyeixient', however; Wil1 be'fbt one-half offits" total'movernnt, dr r'itilit-isrrested'I by the nose 122 of the *secondary latches 1l'8jand 119. 'Atthis time ythe reversing clutch 53' is--inv itsneiitrai position, ftherebystopping'f-tiie The tarry springf12i0vr or15'11urider' 'compression head of "the cyliiider'beingfrnoved will l'he"forced neiitralizing of thev clutch and the engagement.

thereof* with l*the opposite Aclutch Ir'iemb'er. `As

the'head and cylindercontinue tomove, the sec? onda'rylatchfwill be oscillate'd' todi'sp'o'se it'st nosev 121 f above the 'spring frame 96ther'by releasing' the' said frame-ahd'perrnitting th`e 'cdixipr'essed' spring 101 or 102 to"compltey the shifting ofthemovement of` these parts the chaiber between the piston and its vcylinder head faga'in' lle'd' 1. In agrinding inachine of the class described the corribination with a vbed, a table ln'ionted thereon for moveiiieriireiative thereto lin "epee` siteff'direc'stiris, arid a mechai'i'ic'aldi'iv'e iriech'a-v Cil;

table, of means operable by the table for eiecting the reversal thereof, and hydraulically controlled means operable with the reversing means for delaying the operation of said means and thereby eifecting a tarry in the movement of the table prior to each reversal thereof.

2. In a grinding machine of the class described the combination with a bed, a table mounted thereon for movement relative thereto in opposite directions, and a mechanical drive mechanism for eifect'ing the said movements of the table, of means operable by the table for effecting the reversal thereof, and hydraulically controlled means operable with the reversing means for delaying the operation of said means and thereby effecting a tarry in the movement of the table prior to each reversal thereof, said hydraulic tarry means comprising a piston and cylinder mechanism for each end of the movement of the table.

3. In a grinding machine of the class described the combination with a bed, a table mounted thereon for movement relative thereto in opposite directions, and a mechanical drive mechanism for effecting the said movements of the table, of means operable by the table for effecting the reversal thereof, and hydraulically controlled means operable with the reversing means for delaying the operation of said means and .thereby effecting a tarry in the vmovement of the table prior to each reversal thereof, said hydraulic tarry means comprising a piston and cylinder mechanism for each end of the movement of the table, eachof the piston and cylinder mechanisms including an inlet for the hydraulic medium, and a variably controlled outlet whereby the tarry may be changed or varied.

4. In a reversing mechanism for use with machine tool organizations, the combination of a table member or slide, a reversible mechanical drive for saidl table, a load and rire mechanism for eifecting the reverse of the drive, and means for controlling the operation of said load and fire mechanism including a pivoted latch, a yieldably actuated member for actuating the latch to its released position, and hydraulic means for controlling the movement of the latch release member.

5. In a reversing mechanism for use with machine tool organizations, the combination of a table member or slide, a reversible mechanical drive for said table, a load and re mechanism for effecting the reverse of the drive, and means for controlling the operation of said load and fire mechanism including a pivoted latch, a yieldably actuated member for actuating the latch to its released position, and hydraulic means for controlling the movement of the latch release member, said hydraulic` control means including a piston and cylinder movable relative to one another, one of said parts carrying the latch actuating member, and means controlling the flow of an hydraulic medium employable with the piston and cylinder mechanism.

6. In a reversing mechanism for use with machine tool organizations, the combination of a table member or slide, a reversible mechanical drive for said table, a load and re mechanism for effecting the reverse of the drive, and means for controlling the operation of said load and fire mechanism including a pivoted latch, a yieldably actuated member for actuating the latch to its released position, and hydraulic means for controlling the movement of the latch release member, said hydraulic control means including a piston and cylinder movable relative to one an other, one of said parts carrying the latch actuating member, an hydraulic medium for eecting the operation of the piston and cylinder mechanism, a valve controlled inlet for the medium to the piston and cylinder mechanism, and an adjustable valve controlled outlet for the medium whereby the operation of the piston and cylinder mechanism under the yielding means is controlled for correspondingly effecting and determining a tarry in the movement of the table and the duration thereof.

7. In a reversing mechanism for use in controlling the reversal of a member of a. machine tool organization the combination with the said member, and a reversible mechanical drive to said member, of a reversing mechanism for said drive including a clutch shiftable to two operable positions and having a neutral position intermediate same, a load and lire mechanism operable by the table for effecting the movement of the clutch from one operative position to the other. and means operable on said load and re mechanism to limit its movement and stop the clutchv inits neutral position thereby stopping the movement of the table and subsequently releasing said load and lire mechanism to permit the load and firel mechanism to complete its movement.

8. In a reversing mechanism for use in controlling the reversal of a. member of a machine tool organization the combination with the said member, and a reversible mechanical drive to said member, of a reversing mechanism for said drive including a clutch shiftable to two operable positions and having a neutral position intermediate same, a load and fire mechanism operable by the table for effecting the movement of the clutch from one operative position to the other. and means operable on said load and fire mecha nism to limit its movement and stop the clutch in its central position thereby stopping the movement of the table and subsequently releasing said load and re mechanism to permit the load and re mechanism to complete its movement, said means including a stop latch, and yielding means for rendering the stop latch inoperative.

9. In a reversing mechanism for use in oontrolling the reversal of a member of a machine tool organization the combination with the seid member, and a reversible mechanical drive to said member, of a reversing mechanism for said drive Yincluding a clutch shiftable to two operable positions and having a neutral position intermediate same, a load and fire mechanism operable by the table for effecting the movement o! the clutch from one operative position to the other, and means operable on said load and re mechanism to limit its movement and stop the clutch in its neutral position thereby stopping the movement of the table and subsequently releasing said load and fire mechanism to permit the load and fire mechanism to complete its move-l ment, said means including a stop latch, yieldingV means for rendering the stop latch inoperative, and an hydraulically controlled piston and cylinder mechanism for controlling the operation of the stop latch.

10. In a reversing mechanism for use in controlling the reversal of a member of a machine tool organization the combination with the said member, and a reversible mechanical drive to said member, of a reversing mechanism for said drive including a clutch shiftable to two operable positions and having a neutral position'intermediate same, a load and re mechanism operable by the table for effecting the movement of the clutch from one operative position to the other, and means operable on said load and fire mechanism to limit its movement and stop the clutch in its neutral position thereby stopping the movement of the table and subsequently releasing said load and re mechanism to permit the load and re mechanism to complete its movement, said means including a stop latch, yielding means for rendering the stop latch inoperative, an hydraulically controlled piston and cylinder mechanism for controlling the operation of the stop latch, and yielding means for returning the stop latch to its normal operative position.

11. In a reversing mechanism for use with machine tool organizations to effect and control the reversal of a member thereof the combination with the said member, and a reversible drive connected therewith, of a reversing mechanism for said drive including a clutch member, a load and re mechanism for shifting the clutch from one to the other of its operative positions, an arm for actuating the load and fire mechanism through a portion of its movement, a stop latch for limiting the movement of the load and re mechanism and stopping the clutch in its neutral position, yielding means for rendering the stop latch inoperative, and a connection between the stop latch yielding means and arm whereby said yielding means is tensioned simultaneously with the partial operation of the load and fire mechamsm.

12. In a reversing mechanism for use with machine tool organizations to effect and control the reversal of a member thereof the combination with the said member, and a reversible drive connected therewith, of a reversing mechanism for said drive including a clutch member, a load and fire mechanism for shifting the clutch from one to the other of its operative positions, an arm for actuating the load and fire mechanism through a portion of its movement, a stop latch for limiting the movement of the load and fire mechanism and stopping the clutch in its neutral position, yielding means for rendering the stop latch inoperative, a connection between the stop latch yielding means and arm whereby said yielding means is tensioned simultaneously with the partial operation of the load and re mechanism, and hydraulically controlled means for controlling the operation of the stop latch actuating means.

13. In a reversing mechanism for use with machine tool organizations to effect and control the reversal of a member thereof the combination with the said member, and a reversible drive connected therewith, of a reversing mechanism for said drive including a clutch member, a load and ire mechanism for shifting the clutch from one to the other of its operative positions, an arm for actuating the load and re mechanism through a portion of its movement, a stop latch for limiting the movement of the load and fire mechanism and stopping the clutch in its neutral position, yielding means for rendering the stop latch inoperative, a connection between the stop latch yielding means and arm whereby said yielding means is tensioned simultaneously with the partial operation of the load and fire mechanism, and hydraulically controlled means for controlling the operation of the stop latch actuating means, said hydraulically controlled means including a piston and cylinder, an hydraulic medium therefor, abutments on the piston and cylinder and stop latch, and a valve controlling the flow o'the medium.y

ALFRED G. PLIMMER. 

